/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * 
 */

package org.apache.jmeter.protocol.http.modifier;

import java.io.CharArrayWriter;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;

import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;

/**
 * The handler used to read in XML parameter data.
 * 
 * @author Mark Walsh
 * @version $Revision: 493789 $
 */
public class UserParameterXMLContentHandler implements ContentHandler {
	// -------------------------------------------
	// Constants and Data Members
	// -------------------------------------------

	// Note UserParameterXML accesses this variable
	// to obtain the Set data via method getParsedParameters()
	private List userThreads = new LinkedList();

	private String paramname = "";

	private String paramvalue = "";

	private Map nameValuePair = new HashMap();

	/** Buffer for collecting data from the "characters" SAX event. */
	private CharArrayWriter contents = new CharArrayWriter();

	// -------------------------------------------
	// Methods
	// -------------------------------------------

	/*-------------------------------------------------------------------------
	 * Methods implemented from org.xml.sax.ContentHandler
	 *----------------------------------------------------------------------- */
	public void setDocumentLocator(Locator locator) {
	}

	public void startDocument() throws SAXException {
	}

	public void endDocument() throws SAXException {
	}

	public void startPrefixMapping(String prefix, String uri) throws SAXException {
	}

	public void endPrefixMapping(String prefix) throws SAXException {
	}

	public void startElement(String namespaceURL, String localName, String qName, Attributes atts) throws SAXException {

		contents.reset();

		// haven't got to reset paramname & paramvalue
		// but did it to keep the code looking correct
		if (qName.equals("parameter")) {
			paramname = "";
			paramvalue = "";
		}

		// must create a new object,
		// or else end up with a set full of the same Map object
		if (qName.equals("thread")) {
			nameValuePair = new HashMap();
		}

	}

	public void endElement(String namespaceURI, String localName, String qName) throws SAXException {
		if (qName.equals("paramname")) {
			paramname = contents.toString();
		}
		if (qName.equals("paramvalue")) {
			paramvalue = contents.toString();
		}
		if (qName.equals("parameter")) {
			nameValuePair.put(paramname, paramvalue);
		}
		if (qName.equals("thread")) {
			userThreads.add(nameValuePair);
		}
	}

	public void characters(char ch[], int start, int length) throws SAXException {
		contents.write(ch, start, length);
	}

	public void ignorableWhitespace(char ch[], int start, int length) throws SAXException {
	}

	public void processingInstruction(String target, String date) throws SAXException {
	}

	public void skippedEntity(String name) throws SAXException {
	}

	/*-------------------------------------------------------------------------
	 * Methods (used by UserParameterXML to get XML parameters from XML file)
	 *----------------------------------------------------------------------- */

	/**
	 * results of parsing all user parameter data defined in XML file.
	 * 
	 * @return all users name value pairs obtained from XML file
	 */
	public List getParsedParameters() {
		return userThreads;
	}
}
